DNP3 Driver Tag Type Properties: Serial Tab
The Serial Tab of the DNP3 driver tag properties folder is used to set the parameters used to communicate with the driver. If the configured port is using a modem for communications to a DNP3 outstation, this tag may be configured to accept incoming phone calls.
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Enables you to select the serial port tag or TCP/IP tag you wish to be associated with this driver tag. A serial port tag opens a serial port to enable communications between VTS and your PLC or RTU. A TCP/IP tag enables you to connect to a series of hosts, allowing you to transmit data across a network or over the Internet.
The Port field can be cleared using the X button that appears to its right.
The station address for VTS. This is the "from" address in messages from VTS to the RTU, and the "to" address in messages from the RTU to VTS. The range is 0 - 65535.
The Time-Out Limit field indicates the time in seconds or fractions of a second that this driver should wait for a reply from the remote unit.
The station address for the RTU. The valid range is 0 to 65535.
Sets the amount of time (in seconds) that this driver will wait before dropping RTS at the end of a data transmission.
The Retries spin box enables you to select the number of attempts that will be made by this driver if there is no reply to a message. An error will be declared after this number has been reached.
The Hold checkbox indicates whether this driver should hold data from the PLC or RTU in the event of a communications failure.
If the Hold checkbox is selected, the last received value from the PLC or RTU will be held.
If the Hold checkbox is not selected, the data will be invalidated in the event of a communications error.
By default, the Hold checkbox is not selected.
If set, every low level data link message will be confirmed by an acknowledgement. This option is generally used in an environment where there are unreliable communications due to the extra non-data traffic sent.
If set, this registers the driver with the modem manager to accept incoming phone calls from DNP3 outstations. The behavior will vary depending on whether the Enable Unsolicited Data checkbox in the Options tab is checked.
If Enable Unsolicited Data is not checked, each incoming call will be processed as a new link. The communication link initialization sequence will be processed for each.
If Enable Unsolicited Data is checked, then subsequent calls are treated as existing links, thus reducing communication overhead.